2002 GTX DI Water box coupler melting

[Water Rider]

I need some help finding out why I keep melting the orange rubber coupler that connects the exhausts pipe cone. I have blown out all the lines, flushed the cooling system many times, removed and checked the exhaust pipe and muffler for blockage and replaced the water regulator. In total I have melted a hole in 5 different orange rubber exhaust piple couplers in this trial and error process. It take about 30 minutes of just normal riding for the rubber to melt a hole.

Any ideas of where to go from here? Is it a air compressor problem since its a DI? maybe a faulty jet pump not pushing enough water through? can a water box get clogged not letting the gas escape?

Im just stumped.. please help!

 

[Water Rider]

As I continue to run down the rabbit hole...

Does anyone know how the "black rubber Covered Reducer" found on the top of the jet pump housing can effect the cooling system? What would be the symptoms if it was not installed correctly?

It would also be number 44 if you have the SeaDoo Service manual in the Jet Pump Section?

any help is appreciated